From 66706077dc89c66a4777a4c6298273816afb848c Mon Sep 17 00:00:00 2001 From: Thinh Nguyen Date: Thu, 24 Sep 2020 01:21:43 -0700 Subject: usb: dwc3: ep0: Fix ZLP for OUT ep0 requests The current ZLP handling for ep0 requests is only for control IN requests. For OUT direction, DWC3 needs to check and setup for MPS alignment. Usually, control OUT requests can indicate its transfer size via the wLength field of the control message. So usb_request->zero is usually not needed for OUT direction. To handle ZLP OUT for control endpoint, make sure the TRB is MPS size. Cc: stable@vger.kernel.org Fixes: c7fcdeb2627c ("usb: dwc3: ep0: simplify EP0 state machine") Fixes: d6e5a549cc4d ("usb: dwc3: simplify ZLP handling") Signed-off-by: Thinh Nguyen Signed-off-by: Felipe Balbi --- drivers/usb/dwc3/ep0.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) (limited to 'drivers/usb/dwc3/ep0.c') diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c index b0363e3ba4d1..5580caed8b0c 100644 --- a/drivers/usb/dwc3/ep0.c +++ b/drivers/usb/dwc3/ep0.c @@ -947,12 +947,16 @@ static void dwc3_ep0_xfer_complete(struct dwc3 *dwc, static void __dwc3_ep0_do_control_data(struct dwc3 *dwc, struct dwc3_ep *dep, struct dwc3_request *req) { + unsigned int trb_length = 0; int ret; req->direction = !!dep->number; if (req->request.length == 0) { - dwc3_ep0_prepare_one_trb(dep, dwc->ep0_trb_addr, 0, + if (!req->direction) + trb_length = dep->endpoint.maxpacket; + + dwc3_ep0_prepare_one_trb(dep, dwc->bounce_addr, trb_length, DWC3_TRBCTL_CONTROL_DATA, false); ret = dwc3_ep0_start_trans(dep); } else if (!IS_ALIGNED(req->request.length, dep->endpoint.maxpacket) @@ -999,9 +1003,12 @@ static void __dwc3_ep0_do_control_data(struct dwc3 *dwc, req->trb = &dwc->ep0_trb[dep->trb_enqueue - 1]; + if (!req->direction) + trb_length = dep->endpoint.maxpacket; + /* Now prepare one extra TRB to align transfer size */ dwc3_ep0_prepare_one_trb(dep, dwc->bounce_addr, - 0, DWC3_TRBCTL_CONTROL_DATA, + trb_length, DWC3_TRBCTL_CONTROL_DATA, false); ret = dwc3_ep0_start_trans(dep); } else { -- cgit v1.2.3